A Modern, High-performance Kernel

Gentoo Linux 1.4 also contains a new high-performance kernel for x86
systems. Some of our users prefer running stock, -ac, Red Hat, or Mandrake
kernels, which are also fully supported. In fact, we provide ebuilds for
vanilla and Red Hat kernel sources as a convenience for our users. That said,
many have come to appreciate the Gentoo-sources kernel, which includes several
patches to improve performance, scalability, functionality, and hardware
compatibility.

Our new kernel is based upon 2.4.19 and includes Robert Love's preemptive
kernel and scheduler-hints patches, Ingo Molnar's O(1) scheduler and smptimers
patches, and Rik van Riel's reverse mapping patches, for enhanced
responsiveness and scalability under high loads and in high-end multiprocessor
systems.

We provide IBM's EVMS (Enterprise Volume Management System) support. EVMS
is an excellent storage management system providing a single modular API that
supports nearly all of Linux's storage technologies. You can find out more
about IBM EVMS at the EVMS SourceForge
site.

The kernel contains extensive filesystem technology support including ext2,
ext3, ReiserFS, XFS LVM, software RAID, JFS and EVMS. In addition to kernel
support, Gentoo Linux's new LiveCD supports using all these storage
technologies during the initial installation process, so that configuring your
system to have a root EVMS or XFS filesystem is fully supported.

The new Gentoo Linux kernel also includes Andrea Archangeli's excellent
3.5GB user address space patch. This patch allows users to customize how
Linux divides the system's user and kernel address space. Normally, there is a
3-to-1 ratio between user and kernel memory. A 32-bit Linux kernel thus can
only "see" up to 960MB (~1GB) of RAM, with user processes accessing up to 3GB
of virtual memory. By using a 3.5U/0.5K or 2U/2K divide, users can choose a
balance that better suits the intended use and hardware configuration of their
system. For example, a 2U/2K divide will allow a 32-bit Linux kernel to "see"
1960MB of RAM (~2GB) even without enabling "highmem" support. Alternately, a
3.5U/0.5K split plus highmem support can allow VM-hungry applications to access
up to 3.5GB of virtual memory while still allowing (thanks to highmem) access
to multiple gigabytes of physical RAM. This patch is tremendously helpful for
developers who push 32-bit systems to their limits. This patch is also
invaluable for those writing applications that need to access more than 3GB of
virtual memory. For those interested in trying out this patch, you can find it
in one of the kernel directories at http://www.kernel.org/pub/linux/kernel/people/andrea/kernels/v2.4/.

There are several other miscellaneous features, such as the grsecurity security system, the excellent
HTB3 QoS code, gcc-3 support,
and a handful of various hardware compatibility tweaks (SiS 740/961 chipset
support, Pentium 4/Xeon hardware detection fixes, and some VIA chipset fixes).
NFS TCP support and updates and the FreeS/WAN IPSec implementation will also be
popular.

Portage Improvements

The Portage system has been improved extensively since the 1.2 release,
especially in its performance. By using extensive internal caching and
external metadata caching, the new profiler-optimized Portage is now up to 100
times faster in common, day-to-day use. Here is a comprehensive list of
additional major improvements since the Gentoo Linux 1.2 release:

New "LiveCD"

Gentoo Linux 1.4 features a new "liveCD" installation CD that will boot
into a full runtime version of Gentoo Linux. Because of this, this CD not only
serves as an ideal platform for installing Gentoo Linux, but also makes an
ideal rescue/repair CD and portable Gentoo-Linux-on-a-CD system.

The CD provides a full suite of Linux tools and a familiar Gentoo
environment with near-zero RAM overhead thanks to tmpfs. Tools on the CD
include fdisk, ext2, ext3, XFS, ReiserFS filesystem tools, EVMS tools
("evmsn"), parted, and many, many more.

And a "GameCD"

To promote accelerated OpenGL gaming under Linux, we used our LiveCD as the
foundation for a fully self-hosted GameCD featuring the Unreal Tournament 2003
Demo. Our Unreal Tournament 2003 Gentoo LiveCD allows you to play the
Unreal Tournament 2003 Demo using any modern PC with an NVIDIA GeForce 2 or
greater graphics card and a CD-ROM drive. It has full networking, complete OSS
sound support, and additional Creative Soundblaster Live! and Audigy support
included, allowing for the full gaming experience including LAN/Internet play,
EAX environmental audio, and 3D accelerated OpenGL graphics. Weighing in at
approximately 220MB, the CD also serves as a fully-functional Gentoo Linux
installation CD. If you're interested in trying our our GameCD, the best way to
do so is to visit our FreshMeat.net
GameCD page and download the most recent version listed there.

Accelerated OpenGL gaming (Unreal Tournament 2003) on the GameCD

The Unreal Tournament 2003 Gentoo LiveCD is an ideal way to play Unreal
Tournament 2003 on network machines that are normally used for other tasks,
such as in computer labs and offices after hours. We plan to refine our ut2003
CD, developing it into a full-fledged Linux gaming platform. It's a great way
to promote the use of Linux and Linux gaming in general.

Extensive Updates to Portage

Gentoo Linux 1.4 also includes countless improvements to our Portage tree,
the repository that houses all our ebuild scripts. Currently, we have over
2400 ebuild scripts, including full support for GNOME 2, KDE 3.0.3 and
3.1-beta1 (possibly 3.1 if it's ready), and XFree86 4.2.

That's it for this article. In the next article join me as we take an inside look at
Gentoo Linux 1.4. See you then :)